Fix some APR-ization issues:

1) we're using an apr_time_t file mtime, but trying to fit it in
   a time_t entry in the cache and in parameters to the cache
   access routines; use apr_time_t everywhere

2) we need to use apr_fileperms_t instead of mode_t for APR
   file permissions

PR:		6980


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@88443 13f79535-47bb-0310-9956-ffa450edef68